Does the WRX use pulse width modulated injector control?

[Hindsight]

Getting ready to do the wiring and install traction control and need to verify that the WRX ECU doesn't use pulse width modulation for the injectors.

Google searching didn't turn up anything. Thanks!

[Tamra]

ohhhh traction control. Which system are you going with?

We can't do traction control or ABS in E-Mod for autox, unfortunately.

I'll let someone more knowledgeable than me answer your question.

[TouchStone]

Yes, injectors are controlled via PWM.

44917

What unit are you installing?

[Hindsight]

I'm going with the Racelogic unit (the version without launch control because I'll just use an AccessPort for that feature)..... I think. I haven't really found any good alternatives, and the Racelogic unit gets good reviews, but I'm open to suggestions.

[Hindsight]

Yes, injectors are controlled via PWM.

44917

How does fuel flow relate to traction control?

The instructions in the RaceLogic kit state that it doesn't work with PWM type injector control. I'm not exactly sure what they mean by that though since my understanding of injectors is that they typically receive constant 12v power and then a pulsing ground from the ECU which controls their firing rate and thus, flow. So I'm thinking there is something I'm missing here in their description.

To answer your question, the traction control works by cutting all of the fuel to individual injectors (generally one at a time) to lower power levels as-needed during wheel slip.

[TouchStone]

1.4.7 Pulse Width Modulated Injector SignalsEnsure that the engine ECU does not utilise pulse width modulated injector signals which controllimitthe injector current, as this type of signal is not compatible with the traction control.

You'll be fine. I did some more research. The PWM that the manual mentions is for an injector capable of managing pressure and flow rates with a much faster PWM signal. These systems dont have a fuel line return or fuel pressure regulator.

http://www.fuelpumpu.com/news-diagnostics-how-pulse-width-modulated-fuel-delivery-systems-work.aspx

This is terrible, both systems use PWM just in different ways and at different frequencies!

[bbjones121]

You are fine, there are several people with racelogics installed already. My unit is sitting in a box downstairs while I trim my harness. Iwire has also done a couple harnesses for people with the racelogics connections.

[Hindsight]

Thanks guys.

bbjones, where did you get yours? I found one retailer in the states but the price is a few hundred higher than it should be based on the race logic UK site and the current exchange rate (also factoring in shipping from across the pond).

[bbjones121]

I bought mine directly from them. Shipping wasnt very expensive and I got it in two days. Faster than most domestic shipping! Anyway, I think it was still cheaper. FedEx will mail you a VAT fee bill that they pay on your behalf.

[Hindsight]

Cool thanks, I will give them a call directly.